An internet protocol video delivery network based on adaptive streaming techniques can provide many advantages over traditional cable delivery systems, such as greater flexibility, reliability, lower integration costs, new services, and new features. Adaptive streaming, also known as adaptive bitrate (ABR) streaming, is a delivery method for streaming video over Internet Protocol (IP). Adaptive bitrate streaming is a technique for streaming multimedia across computer networks where the source content is encoded at multiple bit rates. Adaptive bitrate (ABR) streaming uses encoders or packagers to provide multiple different bitrates for the same multimedia content (resulting in different quality levels). ABR clients monitor the network and player resources to determine which bitrate to request when streaming content. The ABR client can switch to different bitrates depending on the state of these resources.
In multicast ABR (MABR) solutions (where a particular encoded bitrate is delivered as multicast to remote ABR clients), the system may have to revert to the use of unicast requests in order to retrieve some media segments. For example, during channel change times or ad-breaks, the demand for unicast traffic is likely to peak and may result in excessive congestion throughout the network.
Thus, improved techniques for minimizing unicast bandwidth, particularly during high congestion periods of unicast requests, are desirable.
It is noted that while the accompanying Figures serve to illustrate embodiments of concepts that include the claimed invention, and explain various principles and advantages of those embodiments, the concepts displayed are not necessary to understand the embodiments of the present invention, as the details depicted in the Figures would be readily apparent to those of ordinary skill in the art having the benefit of the description herein.